Liquid crystal displays (LCDs) have been widely applied in electrical products due to the rapid progress of optical and semiconductor technologies. With their advantages of high image quality, compact size, light weight, low driving voltage, low power consumption and various applications, LCDs have been introduced into portable computers, mobile phones, personal digital assistants, and color televisions are becoming the mainstream display apparatus.
Currently, LCDs mostly comprise a liquid crystal panel and a backlight module disposed behind the panel. Therefore, the backlight module is one of the key components of an LCD. According to the position of the backlight source, the backlight module can be an edge-lighting type or a bottom-lighting type in order to provide LCDs with backlight.
Conventional edge-lighting backlight module uses a light guide plate to guide light through an optical filter for optical improvement, thereby forming a uniform planar light. A light source is disposed at one side of the light guide plate for lighting, and the liquid crystal panel is disposed on the light source and the light guide plate.
Currently, LCDs are thinner and lighter, so the backlight module has to reduce thickness and weight, correspondingly. However, the light source is of a fixed thickness. Therefore, it is difficult to reduce the thickness of the edge-lighting backlight module under the fixed thickness of the light source, thus making LCDs difficult to reduce thickness as a result. Furthermore, the light intensity of the backlight module is susceptible to be higher near the light source, and thus the brightness thereof is not uniform.